Engineering Calculator
Ohm's Law & Electric Power Calculator.
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Ohm's Law Triangle
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What is Ohm's Law?
[Image of ohms law triangle]Ohm's Law is the foundation of electrical engineering. It states that the current flowing through a conductor is directly proportional to the voltage across it and inversely proportional to the resistance.
The Magic Triangle:
Cover the variable you want to find, and the triangle tells you what to do:
- V = I × R (Voltage = Current × Resistance)
- I = V / R (Current = Voltage / Resistance)
- R = V / I (Resistance = Voltage / Current)
Understanding Power (P)
Electric Power is the rate at which electrical energy is transferred or used.
Formula: P = V × I (Power = Voltage × Current).
Unit: Watts (W).
Real Life Example
Imagine a standard USB charger:
Voltage: 5 Volts (V)
Current: 2 Amps (A)
Using Ohm's Law, the effective Resistance of the phone being charged is
R = V/I = 5/2 = 2.5 Ω.
The Power delivered is P = V × I = 5 × 2 = 10 Watts.